Credit card rates have soared by up to 2% in the past four months, taking the average interest rate to its highest level in 13 years.

Despite the Bank of England base rate remaining at 0.5% for 25 months the rates on 18 credit cards have increased by between 0.6% and 2%, taking the average credit card interest rate to 19.1%, according to analysis by product comparison site moneyfacts.co.uk.

The biggest increases have been introduced by the Bank of Scotland and Halifax, both belonging to the same banking group partially owned by the taxpayer.

Royal Bank of Scotland and NatWest, banks that were also rescued by the taxpayer after the 2008 banking crisis, have raised some of their credit card rates by 1%.

Moneyfacts spokeswoman Michelle Slade said: "At the start of 2011 card providers moved to a positive order of repayments as recommended by the Office for Fair Trading, which has dented the revenue levels they can earn from customers. Card providers have also been hit by the PPI ruling, which has seen them having to repay money to customers deemed to have been mis-sold the insurance.

"At the same time there has been a sharp increase in the number of providers raising the interest rates charged on their credit cards."

She added it was unlikely that consumers have seen the last of the increases and urged them to either repay their balance in full, so no interest was payable, or look for a better credit card deal. "While credit card interest rates have risen, customers are now being offered the longest ever 0% balance transfer and introductory purchase deals ever seen.

"Providers hope to bank on customers' reluctance to keep switching and can claw back the lost interest during intro periods once they end," she said.

Although Barclaycard has raised the representative interest rate on its Platinum Balance Transfer Visa to 17.5%, the card is offering the longest interest free balance transfer period of 20 months as well as offering a loyalty scheme. Applicants must be 21 and have a minimum income of £20,000.

Virgin Money Mastercard, which has a representative interest rate of 16.8%, is offering interest-free balance transfers for 18 months. Applicants must be 18 years old.